As consumer demand for interactive electronic access to entertainment (e.g. video-on-demand) and information (Internet) in digital format has increased, this demand has effectively exceeded the capabilities of conventional voice-band modems. In response, various delivery approaches have been proposed, such as optical fiber links to every home, direct satellite transmission, and wideband coaxial cable. However, these approaches are often too costly, and cheaper alternatives have emerged, such as the cable modem which uses existing coaxial cable connections to homes and various high bit rate digital subscriber line (DSL) modems which use the existing twisted-pair of copper wires connecting a home to the telephone company central office (CO).
Significant effort has been expended on utilizing existing telephone copper infrastructure and in-home twisted pair cable for communications beyond what is typically available in the DC to 4 kHz ‘plain-old telephone service’ (POTS) frequency band. Digital Subscriber Line (DSL) and Home Phoneline Networking (HPN) are two examples of such effort. Various DSL standards have been developed, including ANSI T1.413 ADSL specification, ITU G.992.1 full-rate ADSL recommendation and ITU G.992.2 splitterless ADSL recommendation, which enable high-speed communications between a subscriber premise and the central office.
In some network configurations, two or more remote terminal (RT) DSL modems are physically connected to a single phoneline where either modem may communicate with the central office (CO) DSL modem. What is desired is to enable these remote terminal modems to communicate with each other without interfering with the connection between one of the remote terminal modems and the central office DSL modem.